Sprocket-band.



No. 747,473. 'PATENTBD DEG. 22,"'19o3. A. s. REED. SPROCKET BAND.

APPLICATION FILED AUG. 30, 1902.

N0 MODEL.

ms ywnms Pavia: cc, wnoraumo. WASHINGYLIN, n, c.

UNITED STATES Patented December 22, 1903.

PATENT OFFICE.

ALBERT S. REED, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TOFLORENCE-HARRIS, OF CHICAGO, ILLINOIS.

SPROCKET-BAND'.

SPECIFICATION formingpart of Letters Patent No. 747,478, dated December22, 1903.

Application filed August 30, 1902. $erial No. 121,572. (No model.)

To aZZ whom it may concern.-

Be it known that I, ALBERT S. REED, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Sprocket-Bands, (CaseNo. 5,) of which the following is a full, clear, concise, and exactdescription.

My invention relates to sprocket-and-chain gearing; and its object is toprovide a device by which the wear of the sprocket and the stretch ofthe chain may be compensated for, so that the gearing may run easily andproperly.

When a sprocket and chain, which were originally designed to fit oneanother, have been in use for some time, it is found that the chain isstretched,so that the pitch of each link is increased, while thesprocket is worn away in such a manner as to decrease the pitch of itsteeth. The chain, therefore, no longer fits the sprocket accurately, sothat the wear and friction are increased and more power is required todrive the gearing. Furthermore, the strain instead of being equallydistributed around the sprocket is brought practically on one tooth, sothat the liability of the sprocket-teeth to break 01f is increased.

I have devised an exceedingly simple and effective means for readjustingthe sprocket and chain to one another, so that they will fit accuratelyand run smoothly. I provide a metal strip perforated to correspond tothe pitch of the sprocket, which is adapted to be passed around thesprocket as a band and fastened in place. This metal strip may be madein long lengths and pieces cut off as required to fit any size sprocket.

I will describe the invention more particularly by reference to theaccompanying drawings, in which- Figure 1 is a plan view of a length ofmy improved sprocket-band. Fig. 2 is a perspective view of a sprocket,showing how the band is applied; and Figs. 3 and 4 are details showinghow the ends of the band are brought together and fastened upon thesprocket.

The same letters of reference are used to designate the same partswherever they are shown.

The metal strip a is provided with rectangular perforations b b atintervals corresponding to the pitch of the sprocket to be fitted, saidperforations being adapted to receive the teeth of the sprocket. Theband is also provided with rivet-holes c 0 between the perforations b.This metal strip may be made and sold in considerable lengths, and therepairman will cut 0E lengths corresponding to the sprocket to'befitted. The band will then be applied to the sprocket, as shown in Fig.2, and the ends thereof brought together and fastened by a rivet, asshown in Figs. 3 and 4:.

When the band is in place, it will be seen that the effective diameterof the sprocketwheel will thus be increased. The sprocketchain willtherefore engage the teeth nearer their endsthat is to say, along alinefarther from the center of the wheelso that the effective pitch of theteeth-that is, the distance from the engaging surface of one tooth to acorresponding surface of the next toothwill be increased to compensatefor the stretching of the chain and the wearing away of the sprocket.

Having thus described my invention, I claim A compensating device forsprocket-wheels comprising a continuous flat strip of sheet metal, saidstrip'having rectangular perforations at intervals corresponding to andadapted to fit over the teeth of a gear-wheel, and intermediaterivet-holes c 0, one between each two of said perforations, whereby asprocket having any number of teeth maybe fitted with said compensatingdevice cut off to the proper length to encircle the sprocket, said striphaving its ends fastened together by rivets passing through theregistering rivet holes in said ends.

In witness whereof Ihereunto subscribe my name this 27th day of August,A. D. 1902.

ALBERT S. REED.

Witnesses:

ELIJAH T. HARRIS, G. D. OSTRUM.

